CASTING PROBLEMS: REASONS AND RESOLUTIONS

·         COMPROMISED CASTING SURFACES

The alloy's or the flask's temperature during casting is the primary cause of the orange skin problem. The calcium sulfate investment may leak gas in the event of excessive heat, which could cause the orange skin condition.

RECOMMENDATION: Verify the casting temperatures and think about reducing them.

·         FINNING OR FLASHING

It can be the result of using too little work time and the wrong ratio of powder to water. Fining may also result from very forceful material casting.

RECOMMENDATION: Use the appropriate volume of water (vacuum investing machines require this in particular). Make sure you have eight minutes to work. Use the appropriate spin for centrifugal casting. Lower pressure while casting in a vacuum. Make sure that the maximum burnout temperature is kept at 750 °C or lower.

·         BLISTER

Either the flasks are dewaxed at an excessive temperature, or the dewax soak time is insufficient, which results in blisters. Additionally, boiling wax that erodes the investment surface results in blisters.

RECOMMENDATION: Increase the duration of the dry dewax process by at least three hours (between 150 and 250°C); nevertheless, don't let the temperature rise above 250°C. Before de-waxing, let flasks sit undisturbed for at least an hour.

·         INVESTMENT CRACKS

Inadequate planning is the main cause of investment failures. This can happen if you use tap water, the mixing period is too lengthy, the water-to-powder ratio is wrong, or the investment has expired.

RECOMMENDATION: Always use distilled water, and use a scale to measure out the necessary amounts of water and investment before beginning the operation by the supplier's recommendations.

·         UNFINISHED PORTIONS OR HOLES DEVELOP

Incomplete castings are mostly caused by low metal temperature and poor spruing. An appropriate tree layout is essential for spin and vacuum casting systems. It is crucial to check the vacuum pump and gas pressure on double-stage casting equipment (vacuum/pressure).

RECOMMENDATION: Make sure the alloy temperature is appropriate and set up the tree such that it fits the patterns you are casting. Examine every part of your casting apparatus.

·         FILLED ENGRAVINGS

Filled engravings are among the most frequent casting problems. First, measure the width and depth dimensions. Never should a text be wider than it is deep. If the writing is not too deep, you can either lower the water quantity by 1 or 2% or let the flask rest for a longer time to invest harder. It is not recommended to use boric acid with our resins.

·         INADEQUATE CASTING

Incomplete casting happens when the flask or metal is too cold or is not sprued correctly.

RECOMMENDATION: Raising the casting temperature is necessary to prevent the metal from freezing before it fills the mold. The metal should be able to enter the sprue system with ease and without obstruction.